Unless you were in college around 1975, you probably never heard the German version of Emerson Lake and Palmer, but Triumvirat's Spartacus is far better than anything ELP did. It's a concept album about a revolt against the Romans by a slave and gladiator named Spartacus, as in the movie with Kirk Douglas.
They didn't have a singer like Greg Lake or an organist who could match Keith Emerson, or a drummer like Carl Palmer. And to make matters worse, they were Germans (you can hear it in some of the mistakenly stressed syllables). But what they lacked in technical chops they made up for in an album that should be on everybody's must play list.
They had a couple other terrific albums; Illusions on a Double Dimple is also highly recommended.
I can't remember a song that started with a better hook. The "pow" about 12 seconds in is completely irresistable. The Moodys had some terrific intros: Ride My See Saw and You and Me are strong contenders.
If they had stayed together in the 1970s, I think they could have been a stadium band; they had a terrific catalog and when they reformed around 1978 they still could bring it. They just missed their wave, but at the top, they were as good as any band has ever been.